Mazda CX-7 2007 Workshop Manual page 351

SYMPTOM TROUBLESHOOTING [L3 WITH TC]
Diagnostic procedure
STEP INSPECTION
1 Connect the M-MDS to the DLC-2.
Access the ECT PID.
Verify that the ECT PID is less than 116°C
{241°F} during driving.
Is ECT PID less than specified?
2 Inspect for the following:
• Air leakage or restriction from intake-air
system
• Fuel quality (proper octane, contamination,
winter/summer blend)
• Exhaust system and/or three-way catalytic
converter (TWC) restriction
• Charge air cooler condition (restriction or
damaged)
Are all items normal?
3 Perform the self-test function using the M-MDS.
Turn the ignition switch to the ON position.
Retrieve any DTCs.
Is a DTC displayed?
4 Inspect the knock sensor.
(See01-40-47 KNOCK SENSOR (KS)
INSPECTION[L3 WITH TC].)
Is the knock sensor normal?
5 Perform the EGR system operation inspection.
(See01-03-78 ENGINE CONTROL SYSTEM
OPERATION INSPECTION[L3 WITH TC].)
Does the EGR system operate properly?
6 Perform the TP sweep inspection.
(See01-03-78 ENGINE CONTROL SYSTEM
OPERATION INSPECTION[L3 WITH TC].)
Does the electronic throttle control system work
properly?
7 Perform the Variable Swirl Control System
Operation Inspection.
(See01-03-78 ENGINE CONTROL SYSTEM
OPERATION INSPECTION[L3 WITH TC].)
Does the variable swirl system work properly?
8 Perform the Wastegate Control System
Operation Inspection.
(See01-03-78 ENGINE CONTROL SYSTEM
OPERATION INSPECTION[L3 WITH TC].)
Does the variable swirl system work properly?
9 Perform the spark test.
(See01-03-78 ENGINE CONTROL SYSTEM
OPERATION INSPECTION[L3 WITH TC].)
Is a strong blue spark visible at each cylinder?
10 Inspect CMP and CKP sensor for the following;
• Installation condition
(See01-40-45 CAMSHAFT POSITION
(CMP) SENSOR REMOVAL/
INSTALLATION[L3 WITH TC].)
(See01-40-42 CRANKSHAFT POSITION
(CKP) SENSOR REMOVAL/
INSTALLATION[L3 WITH TC].)
• Damaged trigger wheel and camshaft
• Open or short circuit in the wiring harnesses
Is there any malfunction detected?
RESULTS
Yes Go to the next step.
No The cause of this concern could be from the cooling
system overheating.
Perform the symptom troubleshooting "NO.17
COOLING SYSTEM CONCERNS - OVERHEATING."
(See01-03-60 NO.17 COOLING SYSTEM
CONCERNS-OVERHEATING[L3 WITH TC].)
Yes Go to the next step.
No Service if necessary.
Repeat Step 2.
Yes DTC is displayed:
Go to the appropriate DTC test.
(See01-02-13 DTC TABLE[L3 WITH TC].)
No No DTC is displayed:
Go to the next step.
Yes Go to the next step.
No Replace the knock sensor.
(See01-40-47 KNOCK SENSOR (KS) REMOVAL/
INSTALLATION[L3 WITH TC]
Yes Go to the next step.
No Inspect or replace the malfunctioning parts, according
to the inspection results.
Yes Visually inspect the throttle body (damaged/
scratching.) If normal, go to the next step.
No Inspect or replace the malfunctioning parts, according
to the inspection results.
Yes Go to the next step.
No Inspect or replace the malfunctioning parts, according
to the inspection results.
Yes Go to the next step.
No Inspect or replace the malfunctioning parts, according
to the inspection results.
Yes Go to the next step.
No Inspect or replace the malfunctioning parts, according
to the inspection results.
Yes Repair or replace the malfunctioning part according to
the inspection results.
No Go to the next step.
ACTION
01-03–51
01-03